WASHINGTON -- The Senate on Wednesday approved far-reaching pension legislation meant to assure that companies with traditional pension plans live up to the promises they make to their workers.

In the face of new warnings about the future solvency of the nation's private pension system, the bill passed 97-2. Debate now moves to the House, which is expected to take up its version of the legislation next month.

"The retirement security of millions of hard-working Americans is at risk,'' said Sen. Edward Kennedy, D-Mass., one of the authors of the legislation the requires companies to fully fund their pension plans and takes steps to improve the gloomy financial outlook of the federal agency that insures private pension plans.

The vote came a day after the Pension Benefit Guaranty Corporation, which insures defined-benefit plans, announced in an annual report that it was now carrying a $22.8 billion deficit and was looking at a future where more bankrupt companies abandon their plans, transferring payment responsibility to the PBGC.

The White House, in a statement, said it supported the Senate bill but opposed provisions that would give airlines more time to fully fund their pensions and other measures that might delay meeting full funding targets. It said the president would be urged to veto legislation if the net effect is to weaken funding requirements relative to current law.

The agency on Tuesday reported the deficit for fiscal 2005, which ended Sept. 30, a year in which big airlines flew into bankruptcy court and dumped their pension liabilities.

Without a legislative overhaul, the PBGC, which is financed by insurance premiums paid by companies and by PBGC's investment returns, eventually will run out of money to pay the claims of retirees of companies whose plans it has assumed, policy-makers warn. That would raise the possibility of a taxpayer bailout.

In its annual report, the PBGC said that as of Sept. 30 it had $56.5 billion in assets to cover $79.2 billion in pension liabilities.

Traditional employer-paid pension plans, giving retirees a fixed monthly amount based on salary and years of employment, are now estimated to be underfunded by some $450 billion.